Adipose-derived adult stromal/stem (ADAS) cells pose exciting opportunities for the field of biomedical engineering. ADAS cells are attractive as a cell source for tissue regeneration procedures because of their ready availability and limited donor-site morbidity. Past research has shown that these cells can be differentiated into a variety of cell types using media supplements, effectively guiding them towards specific lineages of interest: chondrocytic, osteoblastic, and adipocytic. Current studies in our laboratory indicate that fully differentiated cells' and undifferentiated ADAS cells posses biomechanical properties characteristic of their cell type (osteoblast, chondrocyte, adipocyte). The goal of the Mentored phase of the project is to determine how cellular mechanics change during stem cell differentiation. We hypothesize that cellular biomechanical properties reflect the stage of stem cell differentiation and provide a marker for the cell's potential to differentiate into specific phenotypes. To test this, we will determine the elastic and viscoelastic properties of single, ADAS cells during differentiation using atomic force microscopy. Comparison with [unreadable] primary cell types will help determine whether ADAS cells successfully differentiate in terms of cellular [unreadable] biomechanics. Furthermore, quantifying the local mechanics of cells will help in understanding mechanotransduction in these tissues. The Mentored phase studies will significantly improve our understanding of the cellular-level changes that occur during the stem cell differentiation process and lead. Directly to the proposed research for the Independent phase of the award. The goal of this phase is to separate cells within lipoaspirate by their biomechanical properties to produce lineage-specific cell sources that will improve the performance of engineered tissues. We hypothesize that engineered cartilage containing a high percentage of tissue-specific stem cells will possess better mechanical and biochemical properties than constructs seeded with a more heterogeneous harvest population. To test this, we will sort cells from liposuction waste tissue by their biomechanical properties and subsequently evaluate their multipotent character. Tissue engineered cartilage will be grown using normal and sorted cell populations to determine how stem cell enrichment affects the quality of tissue formation. The entire proposed project will produce significant advances in the areas of mechanotransduction, stem cell biology, and tissue engineering. [unreadable] [unreadable] [unreadable] [unreadable]